1. Field of the Invention
The present invention generally relates to aircraft simulation apparatus and techniques and more specifically, to night vision goggle aided flight simulation.
2. Description of Prior Art
Flight simulation allows for the evaluation of increasingly complex systems utilized in aircraft for the purposes of testing and flight training. Simulation may yield evaluation of systems while they are still in the design stage to allow optimization of the design process. Aviator training performance can be enhanced and evaluated for many types of flight situations without the cost or danger of real situations. The current generation of aircraft simulators utilize computerization where realism is provided with cockpit representation (on either a fixed or moving platform), functioning instruments, and visual displays. One type of aircraft simulation which has yet to be adequately simulated is night vision goggle aided flight.
Pilot's night vision goggles are now utilized in sophisticated aircraft environments, such as the Army's Blackhawk and high performance Navy and Air Force aircraft cockpits. This has led to an increasing need for night vision goggle aided flight training, but without associated dangers. Helicopter pilots have reported "disappearances" of roads through green pastures when viewed through night vision enhancement devices. Due to the limitations of the simulators in use today, pilots only encounter such phenomena in actual field training environment. The risk associated with night vision goggle training, where mistakes in perception may have fatal consequences, make the use of aircraft simulators that provide training highly desirable as a substitute for night training flights. While the prior art has reported using night flight simulation none have established a basis for a specific system that is dedicated to the task of resolving the particular problem at hand.
The nighttime conditions presented in the simulator to an aviator wearing night vision goggles are not accurate renditions of what the aviator would see in conducting an actual night flight. The spectral response of the pilots's eyes are significantly different from either the second or third generation goggle's spectral response. Many flight simulator displays do not have the dynamic range necessary to produce a display of the required low radiance. The standard flight simulator display consists of an array of cathode ray tubes (CRTs). These displays must simulate illumination conditions from bright sunlight down to overcast starlight. The dynamic range required is approximately ten orders of magnitude. The simulation of scenes at night is further complicated as to simulate flights around urban or suburban areas such that the displays must accurately display point sources of light. Current Army night vision goggles are filtered so as to not be responsive to blue or green light such that a use of these colors in a normal display is not effective. Current simulation technology results in imagery that is realistic when viewed by the naked eye, but not realistic when viewed through night vision goggles. The restrictive nature of the night vision goggles also require their actual use in the cockpit simulator for effective training.
What is needed in this instance is an apparatus and technique that will allow pilots to use night vision goggles with the current generation of flight simulators so as to gain proficiency with night vision goggles safely.